Phase IV noninferiority controlled randomized trial to evaluate the impact on diagnostic thinking and patient management and the test-retest reproducibility of the Gaxilose test for hypolactasia diagnosis.

The diagnostic accuracy of the Gaxilose test (GT) for hypolactasia diagnosis has already been proved. The objectives of this clinical trial were to demonstrate the noninferiority of the GT compared to the hydrogen breath test (HBT) on the impact on diagnostic thinking and patient management, to evaluate the GT reproducibility with urine accumulated from 0 to 4 hours and from 0 to 5 hours and to assess test safety. We conducted a randomized, parallel, noninferiority clinical trial. Patients with clinical symptoms suggestive of lactose intolerance were screened for inclusion and randomly assigned to the GT arm or the HBT arm of the study. The impact on diagnostic thinking and patient management was analyzed with pretest and posttest questionnaires in which the investigators indicated their estimated probability of hypolactasia diagnosis and the intended management before and after the GT or the HBT (noninferiority margin: -10%). The primary outcome of the study was the impact on diagnostic thinking, expressed as the mean of the absolute values of the differences between the pretest and posttest probabilities of hypolactasia diagnosis. Patients randomized to the GT arm performed also the retest to evaluate the reproducibility of the GT. A total of 147 patients were included in the intend-to-treat (ITT) population. Among them, 74 performed the HBT and 73 performed the GT. The results proved the noninferiority of the GT compared to the HBT on the impact on diagnostic thinking (ImpactGT = 31.74 ± 23.30%; ImpactHBT = 24.28 ± 19.87%; ΔGT-HBT = 7.46%; 95% confidence interval of ΔGT-HBT: 1.55%, infinite) and on patient management. The test-retest reproducibility was better for the GT with urine accumulated from 0 to 5 h: the intraclass correlation coefficient (ICC) was 0.5761, and the Kappa coefficient was 0.7548, indicative of substantial agreement between both tests. No serious adverse events were reported during the study. The GT has an impact on diagnostic thinking and patient management noninferior to that of the HBT, is reproducible and well tolerated. These results prove the clinical benefit of its use in the clinical practice (ClinicalTrials.gov identifier: NCT02636413)

Analytical Validation of a New Enzymatic and Automatable Method for d-Xylose Measurement in Human Urine Samples

Hypolactasia, or intestinal lactase deficiency, affects more than half of the world population. Currently, xylose quantification in urine after gaxilose oral administration for the noninvasive diagnosis of hypolactasia is performed with the hand-operated nonautomatable phloroglucinol reaction. This work demonstrates that a new enzymatic xylose quantification method, based on the activity of xylose dehydrogenase from Caulobacter crescentus, represents an excellent alternative to the manual phloroglucinol reaction. The new method is automatable and facilitates the use of the gaxilose test for hypolactasia diagnosis in the clinical practice. The analytical validation of the new technique was performed in three different autoanalyzers, using buffer or urine samples spiked with different xylose concentrations. For the comparison between the phloroglucinol and the enzymatic assays, 224 urine samples of patients to whom the gaxilose test had been prescribed were assayed by both methods. A mean bias of −16.08 mg of xylose was observed when comparing the results obtained by both techniques. After adjusting the cut-off of the enzymatic method to 19.18 mg of xylose, the Kappa coefficient was found to be 0.9531, indicating an excellent level of agreement between both analytical procedures. This new assay represents the first automatable enzymatic technique validated for xylose quantification in urine

Analytical Validation of a New Enzymatic and Automatable Method for d-Xylose Measurement in Human Urine Samples

Hypolactasia, or intestinal lactase deficiency, affects more than half of the world population. Currently, xylose quantification in urine after gaxilose oral administration for the noninvasive diagnosis of hypolactasia is performed with the hand-operated nonautomatable phloroglucinol reaction. This work demonstrates that a new enzymatic xylose quantification method, based on the activity of xylose dehydrogenase from Caulobacter crescentus, represents an excellent alternative to the manual phloroglucinol reaction. The new method is automatable and facilitates the use of the gaxilose test for hypolactasia diagnosis in the clinical practice. The analytical validation of the new technique was performed in three different autoanalyzers, using buffer or urine samples spiked with different xylose concentrations. For the comparison between the phloroglucinol and the enzymatic assays, 224 urine samples of patients to whom the gaxilose test had been prescribed were assayed by both methods. A mean bias of −16.08 mg of xylose was observed when comparing the results obtained by both techniques. After adjusting the cut-off of the enzymatic method to 19.18 mg of xylose, the Kappa coefficient was found to be 0.9531, indicating an excellent level of agreement between both analytical procedures. This new assay represents the first automatable enzymatic technique validated for xylose quantification in urine

Analytical Validation of a New Enzymatic and Automatable Method for d-Xylose Measurement in Human Urine Samples

Hypolactasia, or intestinal lactase deficiency, affects more than half of the world population. Currently, xylose quantification in urine after gaxilose oral administration for the noninvasive diagnosis of hypolactasia is performed with the hand-operated nonautomatable phloroglucinol reaction. This work demonstrates that a new enzymatic xylose quantification method, based on the activity of xylose dehydrogenase from Caulobacter crescentus, represents an excellent alternative to the manual phloroglucinol reaction. The new method is automatable and facilitates the use of the gaxilose test for hypolactasia diagnosis in the clinical practice. The analytical validation of the new technique was performed in three different autoanalyzers, using buffer or urine samples spiked with different xylose concentrations. For the comparison between the phloroglucinol and the enzymatic assays, 224 urine samples of patients to whom the gaxilose test had been prescribed were assayed by both methods. A mean bias of -16.08 mg of xylose was observed when comparing the results obtained by both techniques. After adjusting the cut-off of the enzymatic method to 19.18 mg of xylose, the Kappa coefficient was found to be 0.9531, indicating an excellent level of agreement between both analytical procedures. This new assay represents the first automatable enzymatic technique validated for xylose quantification in urine.The authors thank IgorMart´ın for his support with statistical analysis, Jos´e Claros and Ricardo Jara from Immunostep for their work in the kit development, and Guillermo Corrales for his technical assistance. The work presented in this manuscript was funded by Venter Pharma S.L., Madrid, Spain.Peer Reviewe

Improving molecular diagnosis of aniridia and WAGR syndrome using customized targeted array-based CGH.

Chromosomal deletions at 11p13 are a frequent cause of congenital Aniridia, a rare pan-ocular genetic disease, and of WAGR syndrome, accounting up to 30% of cases. First-tier genetic testing for newborn with aniridia, to detect 11p13 rearrangements, includes Multiplex Ligation-dependent Probe Amplification (MLPA) and karyotyping. However, neither of these approaches allow obtaining a complete picture of the high complexity of chromosomal deletions and breakpoints in aniridia. Here, we report the development and validation of a customized targeted array-based comparative genomic hybridization, so called WAGR-array, for comprehensive high-resolution analysis of CNV in the WAGR locus. Our approach increased the detection rate in a Spanish cohort of 38 patients with aniridia, WAGR syndrome and other related ocular malformations, allowing to characterize four undiagnosed aniridia cases, and to confirm MLPA findings in four additional patients. For all patients, breakpoints were accurately established and a contiguous deletion syndrome, involving a large number of genes, was identified in three patients. Moreover, we identified novel microdeletions affecting 3' PAX6 regulatory regions in three families with isolated aniridia. This tool represents a good strategy for the genetic diagnosis of aniridia and associated syndromes, allowing for a more accurate CNVs detection, as well as a better delineation of breakpoints. Our results underline the clinical importance of performing exhaustive and accurate analysis of chromosomal rearrangements for patients with aniridia, especially newborns and those without defects in PAX6 after diagnostic screening

Distorsiones, equívocos y ambigüedades. Las ilusiones ópticas en el arte

La muestra plantea un recorrido pensado para motivar la reflexión y el estudio sobre el potencial creativo que han supuesto las ilusiones ópticas a través de la historia del arte y su significación en el arte contemporáneo

PGC-1α deficiency causes spontaneous kidney inflammation and increases the severity of nephrotoxic AKI

PGC‐1α (peroxisome proliferator‐activated receptor gamma coactivator‐1α, PPARGC1A) regulates the expression of genes involved in energy homeostasis and mitochondrial biogenesis. Here we identify inactivation of the transcriptional regulator PGC‐1α as a landmark for experimental nephrotoxic acute kidney injury (AKI) and describe the in vivo consequences of PGC‐1α deficiency over inflammation and cell death in kidney injury. Kidney transcriptomic analyses of WT mice with folic acid‐induced AKI revealed 1398 up‐ and 1627 downregulated genes. Upstream transcriptional regulator analyses pointed to PGC‐1α as the transcription factor potentially driving the observed expression changes with the highest reduction in activity. Reduced PGC‐1α expression was shared by human kidney injury. Ppargc1a−/− mice had spontaneous subclinical kidney injury characterized by tubulointerstitial inflammation and increased Ngal expression. Upon AKI, Ppargc1a−/− mice had lower survival and more severe loss of renal function, tubular injury, and reduction in expression of mitochondrial PGC‐1α‐dependent genes in the kidney, and an earlier decrease in mitochondrial mass than WT mice. Additionally, surviving Ppargc1a−/− mice showed higher rates of tubular cell death, compensatory proliferation, expression of proinflammatory cytokines, NF‐κB activation, and interstitial inflammatory cell infiltration. Specifically, Ppargc1a−/− mice displayed increased M1 and decreased M2 responses and expression of the anti‐inflammatory cytokine IL‐10. In cultured renal tubular cells, PGC‐1α targeting promoted spontaneous cell death and proinflammatory responses. In conclusion, PGC‐1α inactivation is a key driver of the gene expression response in nephrotoxic AKI and PGC‐1α deficiency promotes a spontaneous inflammatory kidney response that is magnified during AKI.Sandra Zazo and Federico Rojo of the IIS‐FJD Biobank (B.0000647). FIS/Fondos FEDER (PI15/00298, CP14/00133, PI16/02057, PI16/01900, ISCIII‐RETIC REDinREN RD016/0009), Sociedad Española de Nefrología, FRIAT, Comunidad de Madrid en Biomedicina B2017/BMD‐3686 CIFRA2‐CM. Grants from the Spanish ‘Ministerio de Economía Industria y Competitividad’ (MINEICO) and FEDER funds (Grant numbers SAF2015‐63904‐R, SAF2015‐71521‐REDC), and from the EC H2020 framework program Grant MSCA‐ITN‐2016‐721236 to MM. Salary support: ISCIII Miguel Servet and to ABS and MDS‐N. ISCIII Sara Borrell to JM‐MM, and Fundación Conchita Rabago to DMS. Consejería de Educación, Juventud y Deporte (Comunidad de Madrid/FSE) to MF‐B.Peer reviewe

Identification of intragenic <i>PAX6</i> deletion in patients with isolated aniridia.

<p>Targeted array-based comparative genomic hybridization (aCGH) analysis identified two deletions involving partial <i>PAX6</i> deletions in two patients. Colored bars represent the genomic positions of the deletions. Schematic representation of the complete intron-exon structure of <i>PAX6</i> is shown. Exons are indicated by colored rectangles that are wider for the coding regions. CGH array data for both individuals is shown. The patient <i>versus</i> reference log2-ratio for the relative hybridization intensities of probes is plotted. Dots with log2-ratio around -1 indicate a heterozygous deletion (green dots), log2-ratio 0 indicates a normal pattern, and +0.6 indicates a heterozygous amplification (red dots). Shaded areas indicate deletions. Genomic coordinates are shown in the x-axis and are based on the Human Genome Assembly hg19. The red bar indicates a ~63 kb deletion encompassing from exon 5a to exon 13 of <i>PAX6</i> found in patient ANIRIDIA-052 (chr11:31,760,458–31,823,847). The grey bar represents a ~3.3 kb deletion encompassing from exon 5a to exon 7 of <i>PAX6</i> gene found in patient ANIRIDIA-039 (chr11:31,820,789–31,824,052).</p